U.S. patent number 6,453,384 [Application Number 09/443,319] was granted by the patent office on 2002-09-17 for spare area management method of optical recording medium.
This patent grant is currently assigned to LG Electronics Inc.. Invention is credited to Yong Hee Han, Yong Cheol Park.
United States Patent |
6,453,384 |
Park , et al. |
September 17, 2002 |
Spare area management method of optical recording medium
Abstract
A spare area management method of an optical recording medium is
disclosed. The spare area management method utilizes an
identification information to indicate whether a primary spare area
is full or a supplementary spare area has been assigned or
extended, as necessary. Also, the present spare area management
method improves the performance of the driver by replacing a defect
block with a spare block nearer to the defect block.
Inventors: |
Park; Yong Cheol (Kyonggi-do,
KR), Han; Yong Hee (Kyonggi-do, KR) |
Assignee: |
LG Electronics Inc. (Seoul,
KR)
|
Family
ID: |
36442052 |
Appl.
No.: |
09/443,319 |
Filed: |
November 19, 1999 |
Foreign Application Priority Data
|
|
|
|
|
Nov 20, 1998 [KR] |
|
|
98-49937 |
|
Current U.S.
Class: |
711/112;
369/53.17; 714/710; G9B/20.059; G9B/20.027; 714/6.32 |
Current CPC
Class: |
G11B
20/1217 (20130101); G11B 20/1883 (20130101); G11B
2220/20 (20130101); G11B 2220/2575 (20130101) |
Current International
Class: |
G11B
20/18 (20060101); G11B 20/12 (20060101); G06F
012/00 () |
Field of
Search: |
;711/112,103
;369/47.14,53.15,53.35,54 ;714/7,710 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Yoo; Do Hyun
Assistant Examiner: Moazzami; Nasser
Attorney, Agent or Firm: Birch, Stewart, Kolasch &
Birch, LLP
Claims
What is claimed is:
1. A spare area management method of an optical recording medium
comprising: assigning an area for a primary and a supplementary
spare area identification information on the optical recording
medium; setting the primary and the supplementary spare area
identification information to indicate the states of a primary
spare area and a supplementary spare area, wherein the primary
spare area and the supplementary spare area are simultaneously
active for a defective block replacement; and utilizing the primary
spare area for a defective block replacement if the supplementary
spare area identification information indicates a full state of the
supplementary spare area, and utilizing the supplementary spare
area for a defective block replacement if the primary spare area
identification information indicates a full state of the primary
spare area.
2. A spare area management method of an optical recording medium
comprising: assigning an area for a primary and a supplementary
spare area identification information on the optical recording
medium; setting the primary and the supplementary spare area
identification information to indicate the states of a primary
spare area and a supplementary spare area; linearly replacing a
defective block with a spare block of either the primary spare area
or the supplementary spare area which is nearer to the defective
block; and linearly replacing a defective block with a spare block
of the primary spare area if the supplementary spare area
identification information indicates a full state of the
supplementary spare area, and linearly replacing a defective block
with a spare block of the supplementary spare area if the primary
spare area identification information indicates a full state of the
primary spare area.
3. A spare area management method of an optical recording medium
comprising: assigning an area for a primary and a supplementary
spare area identification information on the optical recording
medium; setting the primary and the supplementary spare area
identification information to indicate the states of a primary
spare area and a supplementary spare area, wherein data on a
defective block is linearly replaced with a spare block of either
the primary spare area or the supplementary spare area which
results in a shortest linear replacement time; and linearly
replacing a defective block with a spare block of the primary spare
area if the supplementary spare area identification information
indicates a full state of the supplementary spare area, and
linearly replacing a defective block with a spare block of the
supplementary spare area if the primary spare area identification
information indicates a full state of the primary spare area.
4. A spare area management method of an optical recording medium,
the method comprising: assigning an area for a primary and a
supplementary spare area identification information on the optical
recording medium; setting the primary and the supplementary spare
area identification information to indicate the states of a primary
spare area and a supplementary spare area; setting a supplementary
spare area fall flag as the supplementary spare area identification
information to indicate whether the supplementary spare area is
assigned, before an assignment of the supplementary spare area, and
to indicate whether the supplementary spare area is full, after the
assignment of the supplementary spare area; and utilizing the
primary spare area for a defective block replacement if the
supplementary spare area identification information indicates a
full state of the supplementary spare area, and utilizing the
supplementary spare area for a defective block replacement if the
primary spare area identification information indicates a full
state of the primary spare area, wherein the primary spare area and
the supplementary spare area are simultaneously active for a
defective block replacement.
5. A spare area management method of an optical recording medium,
the method comprising: assigning an area for a primary and a
supplementary spare area identification information on the optical
recording medium; setting the primary and the supplementary spare
area identification information to indicate the states of a primary
spare area and a supplementary spare area; setting a supplementary
spare area full flag as the supplementary spare area identification
information to indicate whether the supplementary spare area is
assigned, before an assignment of the supplementary spare area, and
to indicate whether the supplementary spare area is full, after the
assignment of the supplementary spare area; linearly replacing a
defective block with a spare block of either the primary spare area
or the supplementary spare area which is nearer to the defective
block; and linearly replacing a defective block with a spare block
of the primary spare area if the supplementary spare area
identification information indicates a full state of the
supplementary spare area, and linearly replacing a defective block
with a spare block of the supplementary spare area if the primary
spare area identification information indicates a full state of the
primary spare area wherein the primary spare area and the
supplementary spare area are simultaneously active for a defective
block replacement.
6. A spare area management method of an optical recording medium,
the method comprising: assigning an area for a primary and a
supplementary spare area identification information on the optical
recording medium; setting the primary and the supplementary spare
area identification information to indicate the states of a primary
spare area and a supplementary spare area; setting a supplementary
spare area full flag as the supplementary spare area identification
information to indicate whether the supplementary spare area is
assigned, before an assignment of the supplementary spare area, and
to indicate whether the supplementary spare area is full, after the
assignment of the supplementary spare area; and linearly replacing
a defective block with a spare block of the primary spare area if
the supplementary spare area identification information indicates a
full state of the supplementary spare area, and linearly replacing
a defective block with a spare block of the supplementary spare
area if the primary spare area identification information indicates
a full state of the primary spare area, wherein the primary spare
area and the supplementary spare area are simultaneously active for
a defective block replacement, and wherein data on the defective
block is linearly replaced with a spare block of either the primary
spare area or the supplementary spare area which results in a
shortest linear replacement time.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an optical recording medium and
more particularly, to a spare area management method of a
rewritable optical recording medium.
2. Discussion of Related Art
An optical storage medium is generally divided into a read only
memory (ROM), a write once read many (WORM) memory into which data
can be written one time, and rewritable memories into which data
can be written several times. Rewritable optical storage mediums,
i.e. optical discs, include rewritable compact discs (CD-RW) and
rewritable digital versatile discs (DVD-RW, DVD-RAM, DVD+RW).
The operations of writing and playing back data in a rewritable
optical disc may be repeated. This repeated process alters the
ratio of storage layers for recording data into the optical disc
from the initial ratio. Thus, the optical discs lose its
characteristics and generate an error during recording/playback.
This degradation appears as a defect area at the time of
formatting, recording on or playing back from an optical storage
medium. Also, defective areas of a rewritable optical disc may be
caused by a scratch on its surface, particles of dirt and dust, or
errors during manufacture. Therefore, in order to prevent writing
into or reading out of the defective area, management of such
defective areas is necessary.
FIG. 1 shows a defect management area (DMA) in a lead-in area and a
lead-out area of the optical disc to manage a defect area.
Particularly, the data area,is divided into a plurality of zones
for the defect area management, where each zone is further divided
into a user area and a spare area. The user area is where data is
actually written and the spare area is used when a defect occurs in
the user area.
There are four DMAs in one disc, e.g. DVD-RAM, two of which exist
in the lead-in area and two exist in the lead-out area. Because
managing defective areas is important, the same contents are
repeatedly recorded in all four DMAs to protect the data. Each DMA
comprises two blocks of 32 sectors, where one block comprises 16
sectors. The first block of the DMA, called a DDS/PDL block,
includes a disc definition structure (DDS) and a primary defect
list (PDL). The second block of the DMA, called an SDL block,
includes a secondary defect list (SDL). The PDL corresponds to a
primary defect data storage and the SDL corresponds to a secondary
defect data storage.
The PDL generally stores entries of defective sectors caused during
the manufacture of the disc or identified when formatting a disc,
namely initializing and re-initializing a disc. Each entry is
composed of an entry type and a sector number corresponding to a
defective sector. The SDL lists defective areas in block units,
thereby storing entries of defective blocks occurring after
formatting or defective blocks which could not be stored in the PDL
during the formatting. Each SDL entry has an area for storing a
sector number of the first sector of a block having defective
sectors, an area for storing a sector number of the first sector of
a block replacing the defective block, and reserved areas.
Accordingly, defective areas, i.e. defective sectors or defective
blocks, within the data area are replaced with normal or
non-defective sectors or blocks by a slipping replacement algorithm
and a linear replacement algorithm.
The slipping replacement algorithm is utilized when a defective
area is recorded in the PDL. As shown in FIG. 2A, if defective
sectors m and n, corresponding to sectors in the user area, are
recorded in the PDL, such defective sectors are skipped to the next
available sector. By replacing the defective sectors by subsequent
sectors, data is written to a normal sector. As a result, the user
area into which data is written slips and occupies the spare area
in the amount equivalent to the skipped defective sectors. For
example, if two defect sectors are registered in the PDL, the user
area is slipped into two sectors of the spare area and data may
occupy such two sectors of the spare area.
The linear replacement algorithm is utilized when a defective block
is recorded in the SDL or when a defective block is found during
playback. As shown in FIG. 2B, if defective blocks m and n,
corresponding to blocks in either the user or spare area, are
recorded on the SDL, such defective blocks are replaced by good
blocks in the spare area and the data to be recorded in the
defective block are recorded in an assigned spare area.
When replacing defective area with the spare area by utilizing
either the slipping or linear replacement, the spare area may
become full. If the spare area becomes full, a spare full flag is
set to indicate that the spare area is full.
In a disc structure as shown in FIG. 1, a spare full flag exists in
each zone and each spare full flag is set according to the status
of the corresponding zone, i.e. if the zone is full. Therefore,
when the spare area is required for a slipping or linear
replacement, the spare full flag is checked to determine if the
spare area in the corresponding zone is full, i.e. whether the
spare full flag has been s et. If the spare full flag has been set,
a spare area of a zone in which the spare full flag has not been
set is detected and utilized. However, if the spare full flags in
all zones have been set, i.e. there is no more spare area, a
slipping or linear replacement cannot be executed.
The spare area may be allocated in each zone as described above or
may be allocated in a designated portion of the data area. As shown
in FIG. 3, the spare area may be allocated on the top portion of
the data area. In such case, the spare area is called a Primary
Spare Area SA 1. Namely, the data area excluding the primary spare
area becomes the user area.
The primary spare area is assigned in an initial formatting process
without a logical sector number (LSN).
Thus, the primary spare area is assigned when a manufacturer
produces the optical disc or when a user initially formats an empty
disc. Also, the size of the primary spare area depends upon the
size of the user area. For instance, to have an initial data
recording capacity of 4.7 GB, shown in FIG. 3, the primary spare
area of 26 MB is assigned. Moreover, when defective sectors are
registered in the PDL according to the initial formatting or
reformatting of the optical disc, data cannot be recorded in those
defective sectors, reducing the recording capacity. Therefore, to
maintain the initial data recording capacity, a portion of the
primary spare area equivalent to the defective sectors registered
on the PDL slips into or becomes a part of the user area during
formatting. Accordingly, a physical sector number (PSN) of the user
area to which a value of LSN=0 is assigned varies depending upon
the defective sectors registered on the PDL.
If the primary spare area becomes full by slipping or linear
replacement, as shown in FIG. 4A, a new spare area may be assigned,
for example near the end of the user area. Such additional spare
area is called a supplementary spare area (SA-2). If the assigned
supplementary spare area also becomes full, an extension of the
assigned supplementary spare area may be made when necessary as
shown in FIG. 4B.
As described above, the assignment of the primary spare is fixed
while the supplementary spare area is newly assigned or extendable
if necessary. However, in the disc structure as shown in FIGS. 4A
AND 4B, there is a need to indicate separately whether the primary
spare area is full, whether the supplementary spare area has been
assigned, or the status of the supplementary spare area as it is
extended.
SUMMARY OF THE INVENTION
Accordingly, an object of the present invention is to solve at
least the problems and disadvantages of the related art.
An object of the invention is to provide a spare area management
method of an optical recording medium which can indicate whether a
primary spare area is full and whether a supplementary spare area
has been assigned.
Another object of the invention is to provide a spare area
management method of an optical recording medium which can indicate
whether the spare area is available for a linear replacement.
Additional advantages, objects, and features of the invention will
be set forth in part in the description which follows and in part
will become apparent to those having ordinary skill in the art upon
examination of the following or may be learned from practice of the
invention. The objects and advantages of the invention may be
realized and attained as particularly pointed out in the appended
claims.
To achieve the objects and in accordance with the purposes of the
invention, as embodied and broadly described herein, a spare area
management method of an optical recording medium comprises
assigning an area for primary and supplementary spare area
identification information on the optical recording medium;
indicating by means of a primary spare area identification
information whether the primary spare area is full; and indicating
by means of a supplementary spare area identification information
whether the supplementary spare area is available.
Preferably, the supplementary spare area identification information
indicates whether the supplementary spare area is assigned before a
supplementary spare area is assigned, and indicates whether the
supplementary spare area is full after a supplementary spare area
is assigned. Also, if the primary spare area is full, the primary
spare area identification information indicates the full state of
the primary spare area.
If the supplementary spare area identification information
indicates that the supplementary spare area has not been assigned,
the supplementary spare area is assigned and the supplementary
spare area identification information is converted into a value
which indicates the existence of an available supplementary spare
area. If the supplementary spare area identification information
indicates a full state of the supplementary spare area and if the
supplementary spare area is extendible, the supplementary spare
area is extended and the supplementary spare area identification
information is converted into a value which indicates the existence
of an available supplementary spare area.
According to another aspect of the present invention, a spare area
management method of an optical recording medium comprises linearly
replacing a defect block with a spare block from any spare area of
the primary and the supplementary spare areas, depending upon the
defect block. Preferably, the data on the defect block is linearly
replaced with a spare block nearest to the position of the defect
block. The data on the defect block is linearly replaced with a
spare block of the spare area in which a linear replacement time
would be shortest. Also, the data on the defect block is linearly
replaced with a spare block of a spare area which is not full.
These and other objects of the present application will become more
readily apparent from the detailed description given hereinafter.
However, it should be understood that the detailed description and
specific examples, while indicating preferred embodiments of the
invention, are given by way of illustration only, since various
changes and modifications within the spirit and scope of the
invention will become apparent to those skilled in the art from
this detailed description.
BRIEF DESCRIPTION OF THE ATTACHED DRAWINGS
The invention will be described in detail with reference to the
following drawings in which like reference numerals refer to like
elements wherein:
FIG. 1 shows a data area configuration of a general optical disc in
the related art;
FIG. 2A shows a slipping replacement method for a defect area in
the related art;
FIG. 2B shows a linear replacement method for a defect area in the
related art;
FIG. 3 shows a spare area assigned at the top portion of the data
area;
FIGS. 4A and 4B show a supplementary spare area assigned and
extended on the disc where the primary spare area is assigned as in
FIG. 3;
FIG. 5 shows a structured where flags are added to indicate whether
a primary spare area is full and a supplementary spare area is used
on the optical recording medium according to an embodiment of the
present invention;
FIGS. 6A to 6C are exemplary views illustrating primary and
supplementary spare area flags whose values are varied in
accordance with the status of the primary spare area and the
supplementary spare area according to an embodiment of the present
invention;
FIGS. 7A to 7C are another exemplary views illustrating primary and
supplementary spare area flags whose values are varied in
accordance with the status of the primary spare area and the
supplementary spare area according to an embodiment of the present
invention; and
FIG. 8 shows a linear replacement of the data on a defect block
with the spare area nearest the defect block in a defect area
management method of an optical recording medium according to the
present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Reference will now be made in detail to the preferred embodiments
of the present invention, examples of which are illustrated in the
accompanying drawings.
The present invention is generally directed to a spare area
management method of an optical recording medium which can indicate
by means of identification information whether a primary spare area
assigned on the top portion of data area is full or a supplementary
spare area assigned on the bottom portion of the data area is
available.
The identification information is recorded independently from the
primary and supplementary spare areas. In the present invention,
for the convenience of an explanation, the identification
information for indicating whether the primary spare area is full
will be called `a primary spare area full flag` and the
identification information for indicating whether the supplementary
spare area is assigned or available will be called `a supplementary
spare area full flag`.
FIG. 5 shows a data structure where the primary and supplementary
spare area full flags are added on the optical recording medium
according to an embodiment of the present invention. Particularly,
the primary and supplementary spare area full flags may be added on
a non-used area of the DMA, particularly the SDL or DDS. The
primary and supplementary spare area full flags are added to
indicate whether the primary and supplementary spare areas are
full, respectively.
For example, if the primary spare area is available, i.e. the spare
block for a linear replacement is left, the primary spare area full
flag is reset to a value of `0`. If the spare block is not
available, i.e. the spare area is full, the primary spare area full
flag is set to a value of `1`.
Unlike the primary spare area full flag, the supplementary spare
area full flag is set differently before and after an assignment of
the supplementary spare area. Namely, the supplementary spare area
full flag is added to indicate whether the supplementary spare area
has been assigned before the assignment of the supplementary spare
area, and added to indicate whether the supplementary spare area is
full after the assignment of the supplementary spare area.
For example, if the supplementary spare area has not been assigned,
the supplementary spare area full flag is set to a value of `1`,
and when the supplementary spare area is assigned, the
supplementary spare area full flag is set to a value of `0`. After
the supplementary spare area has been assigned, however, if there
is available area within the supplementary spare area, i.e. the
spare block for the linear replacement is left, the supplementary
spare area full flag remains the value of `0`. Thereafter, once the
spare block is not available, i.e. the spare area is full, the
supplementary spare area full flag is set to the value of `1`.
Also, the method of assigning and extending the supplementary spare
area may be classified into two methods. Generally, in the first
method according to the present invention, if the primary spare
area is full, the supplementary spare area is assigned and if the
assigned supplementary spare area is full, the supplementary spare
area is extended. In the second method according to present
invention, if a predetermined area, for example 1 MB, is left
within the primary spare area, the supplementary spare area is
assigned and if a predetermined area is left within the
supplementary spare area, the supplementary spare area is
extended.
The second method may utilize one active mode, in which the
supplementary spare area is assigned when the primary spare area is
still left, but is not used for the linear replacement until the
primary spare area is full. Similarly, the extended supplementary
spare area is not used for the linear replacement until the
assigned supplementary spare area is full. Namely, the one active
mode means that the primary and supplementary spare areas are not
simultaneously active and when the supplementary spare area is
extended, the supplementary spare areas are not simultaneously
active.
The various states of the primary and supplementary spare area full
flags in the one active mode are shown in FIGS. 6A.about.C and
FIGS. 7A.about.C according to the embodiments of the present
invention.
Referring to FIGS. 6A to 6C, the primary spare area is assigned
upon formatting, and if necessary, i.e. if the primary spare area
is full, the supplementary spare area is assigned. Thereafter, if
the assigned supplementary spare area becomes full, the
supplementary spare area is extended. In particular, upon
formatting, the primary spare area full flag is reset to a value of
`0` and the supplementary spare area full flag is set to a value of
`1`, as shown in FIG. 6A. Next, if the primary spare area is full
for the linear replacement, the primary spare area full flag is set
to a value of `1`, also shown in FIG. 6A. Since the primary spare
area is not extendable, the primary spare area full flag remains
the value of `1`, as shown in FIGS. 6B and 6C.
The identification information for the spare area which
differentiates the assignment, full state and extension of the
supplementary spare area is by means of the supplementary spare
area full flag. For example, the supplementary spare area full flag
is initially set to a value of `1` as shown in FIG. 6A in a state
where the supplementary spare area has not been assigned. If the
supplementary spare area is assigned as necessary, the
supplementary spare area full flag is reset to a value of `0`.
Thus, when the primary spare area is full and the supplementary
spare area is newly assigned, the primary spare area full flag
remains a value of `1` and the supplementary spare area full flag
is reset to the value `0`, as shown in FIG. 6B.
Thereafter, if the assigned supplementary spare area becomes full
for a linear replacement, the supplementary spare area full flag is
set to a value of `1`, as shown in FIG. 6B. However, if the
supplementary spare area is extended, the supplementary spare area
is then reset to the value of `0`. In other words, since the
supplementary spare area is extendable, the supplementary spare
area full flag is repetitively reset to the value of `0` from the
value of `1` each time the spare area is extended, as shown in FIG.
6C. However, when the supplementary spare area cannot be further
extended, the supplementary spare area full flag maintains at the
value of `1`.
Referring to FIGS. 7A to 7C, in another example, the primary spare
area is also assigned upon a formatting, and the supplementary
spare area is assigned if a predetermined area within the primary
spare area is left. Thereafter, if a predetermined area within the
assigned supplementary spare area is left, the supplementary spare
area is extended. In particular, upon a formatting the primary
spare area full flag is reset to a value of `0` and the
supplementary spare area full flag is set to a value of `1`, as
shown in FIG. 7A. Next, if a predetermined area in the primary
spare area for the slipping or linear replacement is left, the
supplementary spare area is assigned. At this time, the
supplementary spare area full flag is converted from the value of
`1` to a value `0`, as shown in FIG. 7B. However, since the primary
spare area is not full, the primary spare area full flag maintains
the value of `0`. Once the primary spare area becomes full, the
primary spare area full flag is set to the value `1`. Because the
supplementary spare area is assigned and extended in the one active
mode, the supplementary spare area is not used for a linear
replacement before the primary spare area becomes full, even if the
supplementary spare area has been already assigned.
Similarly, if a predetermined area within the assigned
supplementary spare area is left, the supplementary spare area is
additionally extended. At this time, the supplementary spare area
full flag maintains the value `0` since the supplementary spare
area would not be in a full state due to an extension. If the
supplementary spare area cannot be further extended, the
supplementary spare area full flag is set to a value of `1`, as
shown in FIG. 7C.
In the above embodiment, the supplementary spare area may not be
further extended because data is recorded in the area needed for
the extension of the supplementary spare area. In such case, the
supplementary spare area full flag is reset to the value of `0` if
data recorded on the area to be extended is erased and thereby the
supplementary spare area is extended. However, once the
supplementary spare area cannot be further extended, the
supplementary spare area full flag is set to a value of `1`, as
shown in FIG. 7C.
Moreover, since the supplementary spare area is assigned and
extended in the one active mode, the extended supplementary spare
area is not used for a linear replacement before the assigned
supplementary spare area becomes full, even if the supplementary
spare area is already extended in a state where a predetermined
area within the supplementary spare area is left.
In the above embodiments, the primary spare area is assigned prior
to the assignment of the supplementary spare area. However, the
primary and supplementary spare areas may be simultaneously
assigned upon a formatting, in which the primary and supplementary
spare area full flags are all reset to a value of `0`.
Furthermore, when the spare area is active in the one active mode,
the performance of a linear replacement may be degraded. Namely,
the linear replacement method is executed by moving an optical
pick-up to and from the spare area to record the data of the defect
block on a replacement block in the spare area. However, since the
spare area exists on certain parts of the data area, the
replacement time period for a defect block far from the spare area
can be substantial. To solve this problem, the spare area may be
active in a two active mode.
When a defect block is discovered during a recording or playback of
data from the optical disc in which a spare area has been assigned,
the defect block is replaced with a spare block of the spare area
nearest to the defect block, as shown in FIG. 8. By replacing the
defect block with a nearby spare area, the performance of the drive
can be significantly improved. At this time, if only the primary
spare area is assigned, the primary spare area is used for a linear
replacement. However, when both the primary and supplementary spare
areas are assigned, an appropriate spare area, i.e. a nearby spare
area, is used for a linear replacement.
In this two active mode, the data of a defective block is linearly
replaced with a spare block of the spare area located at a position
which results in the shortest moving distance of the optical
pick-up. If all assigned spare areas are active irrespective of
whether the spare area is the primary or supplementary spare area,
and if a spare block within the primary and supplementary spare
areas is left, the data of a defective block is linearly replaced
with a spare block of any area within the primary or supplementary
spare area which meets the above criteria. For example, the data of
a defective block on the inner peripheral side of an optical
medium, i.e. near the top of the data area, is linearly replaced
with a spare block of the primary spare area. On the other hand,
the data of a defective block on the outer peripheral side of an
optical medium, i.e. near the bottom of the data area, is linearly
replaced with a spare block of the supplementary spare area.
Unlike the one active mode in the two (multiple) active mode, the
entire supplementary spare area would be active irrespective of
whether an area is an extension. Also, when both the primary and
supplementary spare areas are simultaneously active, the spare area
to be used for a linear replacement is determined by first checking
whether each spare area is full.
For example, if a defective block is nearer to the primary spare
area, the primary spare area full flag is checked. At this time, if
the primary spare area full flag is set to a value of `0` as shown
in FIG. 7, the data of the defective block is linearly replaced
with a spare block of the primary spare area. On the other hand, if
the primary spare area full flag is set to a value of `1`, the
supplementary spare area full flag is checked. If the supplementary
spare area full flag is set to a value of `0` as shown in FIG. 7,
the data of the defective block is linearly replaced with a spare
block of the supplementary spare area. This is generally shown in
FIG. 8.
Therefore, upon a detection of a defective block, if any one of the
spare area is full, the spare area in the full state is not used
for a linear replacement. Also, if the supplementary spare area is
additionally extended, the supplementary spare area full flag is
reset to a value of `0` until the supplementary spare area cannot
be further extended, as described with reference to the one active
mode.
Thus, when the supplementary spare area cannot be extended, the
supplementary spare area full flag is set to a value of `1` as
shown in FIG. 7. Accordingly, if both of the primary and
supplementary spare area full flags are set to the value of `1`, a
defective block management cannot be further performed using a
slipping or linear replacement.
As set forth above, a spare area management method of an optical
recording medium according to the present invention can indicate by
means of an identification information whether a primary spare area
is full or a supplementary spare area has been assigned or
extended, as necessary. Thus, the present invention indicates when
a linear replacement cannot be executed because the spare area is
in a full state. In addition, a spare area management method of an
optical recording medium according to the present invention can
replace a defective block with the spare block of the spare area
nearer to the defective block, thereby improving the driver's
performance upon the linear replacement. Moreover, the present
invention is applicable to any optical or other type of medium
having the same format with an assignment of primary spare area and
a supplementary spare area.
The foregoing embodiments are merely exemplary and are not to be
construed as limiting the present invention. The present teachings
can be readily applied to other types of apparatuses, systems,
and/or mediums. The description of the present invention is
intended to be illustrative, and not to limit the scope of the
claims. Many alternatives, modifications, and variations will be
apparent to those skilled in the art.
* * * * *